The first objective (LOLA) of this integrated trial is to determine whether laparoscopic lavage leads to better clinical outcomes compared to sigmoidectomy in patients with perforated diverticulitis with purulent peritonitis in terms of mortality and major morbidity. The second objective (DIVA) is to determine whether sigmoidectomy with anastomosis or sigmoidectomy with end-colostomy is the superior approach in patients with perforated diverticulitis with either purulent or faecal peritonitis in terms of stoma free survival. The study is designed as a multicenter and randomised trial.